Elbow-bending machine



' 1622 426 March 29,1921, F W. ENGELKE ,f a

ELBOW BENDING MACHINE Filed March 22, 192,4`

` f 24x25 F76] Patented Mar. 29, 1927.

UNITED STATES FREDERICK `W. ENGELKE, OF ST. LOUIS, MISSOURI.

ELBOW-BENDING MACHINE.

Application filed March 22, 1924. Serial No. 700,997.

This invention relates to elbow bending machines and the main object is to provide a machine that is especially adapted for bending the throat of an elbow in a pipe ot rectangular cross section. Another object is to provide a machine that can be adjusted for an elbow of any size and gauge. A fui ther object is to provide a practical and eilicient device for the purpose described. lhese and other objects will be apparent -from the accompanying drawing and specification.

In the drawing# Figure l is a vertical section;

Figure 2 is a horizontal section, the throat of an elbow being shown in dotted lines;

Figure 3 is a detail of the hammer and hammer actuating mechanism g Figure 4 is a detail of the cam;

Figure 5 is a modified view of a hammer actuating mechanism;

Figure 6 is a cross section of the throat oi a rectangular elbow before being bent;

Figure 7 is a cross section of the throat of a rectangular elbowv after being bent.

In carrying out this invention I provide a sectional machine block 1 provided with bolt holes 3 for securing the said sectionsI together by means of bolts 2. A hammer recess 4 is provided in the upper central portion of the said bolted sections 1. A slot 8 is cut transversely of the sections 1 below the hammer recess 4 and terminates in a bearing recess 6. A roller recess 5 is cut in a lower medial portion of the said sections adjacent the slot 8 and in line with an anvil recess 7; the said recess 7 being located immediately below the hammer recess 4. A square hammer 11 formed with a collar 12 and carrying a spring 13 upon its shank is mounted in the recess 4 for a purpose to be later explained. An anvil 21 is mounted upon a resilient member 22 which is located in the said anvil recess 7 and is adapted to be engaged by the hammer 11. The said anvil 21 can be readily adjusted by means of an adjustment screw 23 which engages an adjustment screw hole 10. Bearings 24 carrying a heavy steel roller 26, which is located in the roller recess 5, are slidingly mounted in the bearing recesses 6. Adjustment takeup springs 25 are located in the bearing recesses 6 in back of the bearings 24 and are provided to keep the roller 26 bearing against the anvil 21 for a purpose to be later explained. Pressure` equalizing screws 27 are mounted in screw holes 9 and are adapted to bear against the springs 25. A hammer actuating mechanism comprising *a 'shaft 17 carrying a lcam 2O and a pulley 19 60 is journaled in a bearing 29 which is secured to a side of the machine block 1 in line with the hammer 11. A trip bar 14 pivotally mounted in a support 15 which is located upon the said machine block 1 65 medially between the hammer' 11 and the bearing 29. The one end 16 of the said trip bar 14 is pivotally secured to the said hammer 11 while the opposite end 18 is adapted to engage the cam 20 as shown in Figure 3. 70 The said machine block 1 is mounted upon a frame 28 as particularly shown in Figiire 2; the said frame being 4devoid of any braces whatsoever, to prevent interference in the efficient operation of the machine and forming of the work.

In operation the inner throat 30 of a l square elbow is channel shaped as shown in Figure 6 and consists of a web 31 rovided with vertically formed flanges 32. In S0 the construction of the square elbows it is common practice to beat the flanges 32 so as to permit bending the said throat 30 which is readily accomplished in this invention by placing the said flanges upon the anvil 21 S5 and adjusting the bearings 24 so that the roller 26 will bear against the web 31 with considerable pressure. The rotation of the shaft 17 causes the cam 2O to depress the end 18 of the trip bar 14 thereby raising 90 the hammer 11 through the pivotal arrangement of the said trip bar 14 and creating a tension upon the spring 13 which is mounted over the said hammer 11 thereby causing the said hammer to hitthe flange 32 upon the anvil block 21 with considerable force thus flaring the same when the end 18 of the said trip bar 14 engages the ofi'set formed in the cam 20. During this flaring operation the operator exerts considerable muscular energy upon the throat 30 while passing the same over the anvil block 21 thereby torming the same as shown by the dotted lines in Figure 2. After the one flange has been formed the said throat is turned around and the operation repeated upon the other flange. The said operation may be repeated upon both flanges until the desired angle has been formed in the throat.

In the above mentioned process, the action of the hammer hitting the flange V32 upon the anvil block 21 is to cause the said flange tev expand along its outer periphery, whereby the flange is caused to assume an arcuate shape. It is Obvious that only a portion of the desired angle can be obtained in one passage of the throat through the machine since the resistance of the opposite flange will prevent any more curvature being obtained than the elasticity of the material will allow. However, by turning the throat around this difiiculty may be avoided and the other flange caused to assume an arcuate shape, the total curvature thereof being constrained by the elasticity of the material as before. By this means, after a number of passages through the machine, the desired angle will be formed in the throat.

In the modified view the trip bar ll is supplanted by a crank formed in the shaft 17. v

`While I have herein described a certain specific method of constructing and assembling the elements of my invention, it is understood same may be varied in minor details, not departing from the spirit of my invention as deiined in the appended claims.

I claim:

1. In a machine for bending the throat of an elbow in a pipe of rect-angular cross sec tion, a frame, a machine block rigidly ses cured to said frame and having hammer, anvil, roller, and bearing recesses, a slot and roller and anvil adjustment screw holes provided therein; a hammer mounted in the hammer recess; a collar rigidly secured to the hammer; a spring mounted on the hammer; a bar, pivotally mounted on the machine block, engaging the hammer; a shaft journaled to the machine block; a pulley rigidly secured to the shaft; a cam rigidly secured to the shaft engaging the bar; a resilient member located in the anvil recess; an anvil mounted below the hammer in the anvil recess upon the resilient member; an anvil adjusting screw engaging the anvil adjusting screw hole, bearing against the resilient member for adjusting the anvil;

neeaaze springs located in the bearing recesses; bearings mounted in the l'iearing recesses; a roller located in the roller recess, journaled in the bearings; roller adjustmentscrews engaging the roller adjustment screw holes, bearing against the springs in the bearing recesses for adjusting the rolls.

2. A device of the kind described, comprising a frame, a sectionally constructed machine block secured to said frame and having hammer, anvil, roller and bearing recesses, and a slot provided therein; means for securing the sectionally constructed machine blocl; together; a hammer, having a collar incorporated therein, and a spring mounted thereon, mounted in the hammer rec s; a bar, pivotally mounted on the machine block, engaging the hammer; a shaft journaled to the machine block; a pulley rigidly secured to the shaft; a cam, rigidly secured to the shaft, engaging the bar; a resilient member located in the anvil recess; an anvil mounted below the hammer in the anvil recess upon the resilient member; means for adjusting the anvil for different gauges of metal; bearings mounted in the bearing recesses; a roller located in the roller recess, liournaled in the bearings; means for adjusting the roller.

A device of the lind described, comprising a sectionally constructed machine block, having hammer, anvil, roller and bearing recesses and a slot provided therein; means for securing the sectionally constructed machine block together; a hammer, have ing a collar incorporated therein and a spring mounted thereon, mounted in the hammer recess; means for actuating the hammer; an anvil mounted in the anvil rccess below the hammer; bearings mounted in the bearing recesses; and a roller located in the roller recess, journaled in the bearings in the bearing recesses.

In testimony whereof I aiix my signature.

FREDERICK IV. ENGELKE. 

